+Libguestfs provides access to a large part of the LVM2 API, such as
+C<guestfs_lvcreate> and C<guestfs_vgremove>. It won't make much sense
+unless you familiarize yourself with the concepts of physical volumes,
+volume groups and logical volumes.
+
+This author strongly recommends reading the LVM HOWTO, online at
+L<http://tldp.org/HOWTO/LVM-HOWTO/>.
+
+=head2 DOWNLOADING
+
+Use C<guestfs_cat> to download small, text only files. This call
+is limited to files which are less than 2 MB and which cannot contain
+any ASCII NUL (C<\0>) characters. However it has a very simple
+to use API.
+
+C<guestfs_read_file> can be used to read files which contain
+arbitrary 8 bit data, since it returns a (pointer, size) pair.
+However it is still limited to "small" files, less than 2 MB.
+
+C<guestfs_download> can be used to download any file, with no
+limits on content or size (even files larger than 4 GB).
+
+To download multiple files, see C<guestfs_tar_out> and
+C<guestfs_tgz_out>.
+
+=head2 UPLOADING
+
+It's often the case that you want to write a file or files to the disk
+image.
+
+For small, single files, use C<guestfs_write_file>. This call
+currently contains a bug which limited the call to plain text files
+(not containing ASCII NUL characters).
+
+To upload a single file, use C<guestfs_upload>. This call has no
+limits on file content or size (even files larger than 4 GB).
+
+To upload multiple files, see C<guestfs_tar_in> and C<guestfs_tgz_in>.
+
+However the fastest way to upload I<large numbers of arbitrary files>
+is to turn them into a squashfs or CD ISO (see L<mksquashfs(8)> and
+L<mkisofs(8)>), then attach this using C<guestfs_add_drive_ro>. If
+you add the drive in a predictable way (eg. adding it last after all
+other drives) then you can get the device name from
+C<guestfs_list_devices> and mount it directly using
+C<guestfs_mount_ro>. Note that squashfs images are sometimes
+non-portable between kernel versions, and they don't support labels or
+UUIDs. If you want to pre-build an image or you need to mount it
+using a label or UUID, use an ISO image instead.
+
+=head2 LISTING FILES
+
+C<guestfs_ll> is just designed for humans to read (mainly when using
+the L<guestfish(1)>-equivalent command C<ll>).
+
+C<guestfs_ls> is a quick way to get a list of files in a directory
+from programs, as a flat list of strings.
+
+C<guestfs_readdir> is a programmatic way to get a list of files in a
+directory, plus additional information about each one. It is more
+equivalent to using the L<readdir(3)> call on a local filesystem.
+
+C<guestfs_find> can be used to recursively list files.
+
+=head2 RUNNING COMMANDS
+
+Although libguestfs is a primarily an API for manipulating files
+inside guest images, we also provide some limited facilities for
+running commands inside guests.
+
+There are many limitations to this:
+
+=over 4
+
+=item *
+
+The kernel version that the command runs under will be different
+from what it expects.
+
+=item *
+
+If the command needs to communicate with daemons, then most likely
+they won't be running.
+
+=item *
+
+The command will be running in limited memory.
+
+=item *
+
+Only supports Linux guests (not Windows, BSD, etc).
+
+=item *
+
+Architecture limitations (eg. won't work for a PPC guest on
+an X86 host).
+
+=item *
+
+For SELinux guests, you may need to enable SELinux and load policy
+first. See L</SELINUX> in this manpage.
+
+=back
+
+The two main API calls to run commands are C<guestfs_command> and
+C<guestfs_sh> (there are also variations).
+
+The difference is that C<guestfs_sh> runs commands using the shell, so
+any shell globs, redirections, etc will work.
+
+=head2 CONFIGURATION FILES
+
+To read and write configuration files in Linux guest filesystems, we
+strongly recommend using Augeas. For example, Augeas understands how
+to read and write, say, a Linux shadow password file or X.org
+configuration file, and so avoids you having to write that code.
+
+The main Augeas calls are bound through the C<guestfs_aug_*> APIs. We
+don't document Augeas itself here because there is excellent
+documentation on the L<http://augeas.net/> website.
+
+If you don't want to use Augeas (you fool!) then try calling
+C<guestfs_read_lines> to get the file as a list of lines which
+you can iterate over.
+
+=head2 SELINUX
+
+We support SELinux guests. To ensure that labeling happens correctly
+in SELinux guests, you need to enable SELinux and load the guest's
+policy:
+
+=over 4
+
+=item 1.
+
+Before launching, do:
+
+ guestfs_set_selinux (g, 1);
+
+=item 2.
+
+After mounting the guest's filesystem(s), load the policy. This
+is best done by running the L<load_policy(8)> command in the
+guest itself:
+
+ guestfs_sh (g, "/usr/sbin/load_policy");
+
+(Older versions of C<load_policy> require you to specify the
+name of the policy file).
+
+=item 3.
+
+Optionally, set the security context for the API. The correct
+security context to use can only be known by inspecting the
+guest. As an example:
+
+ guestfs_setcon (g, "unconfined_u:unconfined_r:unconfined_t:s0");
+
+=back
+
+This will work for running commands and editing existing files.
+
+When new files are created, you may need to label them explicitly,
+for example by running the external command
+C<restorecon pathname>.
+
+=head2 SPECIAL CONSIDERATIONS FOR WINDOWS GUESTS
+
+Libguestfs can mount NTFS partitions. It does this using the
+L<http://www.ntfs-3g.org/> driver.
+
+DOS and Windows still use drive letters, and the filesystems are
+always treated as case insensitive by Windows itself, and therefore
+you might find a Windows configuration file referring to a path like
+C<c:\windows\system32>. When the filesystem is mounted in libguestfs,
+that directory might be referred to as C</WINDOWS/System32>.
+
+Drive letter mappings are outside the scope of libguestfs. You have
+to use libguestfs to read the appropriate Windows Registry and
+configuration files, to determine yourself how drives are mapped (see
+also L<virt-inspector(1)>).
+
+Replacing backslash characters with forward slash characters is also
+outside the scope of libguestfs, but something that you can easily do.
+
+Where we can help is in resolving the case insensitivity of paths.
+For this, call C<guestfs_case_sensitive_path>.
+
+Libguestfs also provides some help for decoding Windows Registry
+"hive" files, through the library C<libhivex> which is part of
+libguestfs. You have to locate and download the hive file(s)
+yourself, and then pass them to C<libhivex> functions. See also the
+programs L<hivexml(1)>, L<hivexget(1)> and L<virt-win-reg(1)> for more
+help on this issue.
+
+=head1 CONNECTION MANAGEMENT